JP6560720B2 - Hydraulic control device - Google Patents

Description

  The present invention relates to a hydraulic control device that supplies oil from a pump driven by a motor to a hydraulic operation part of a transmission.

  For example, in a vehicle transmission, a hydraulic control in which a second pump (electric pump) driven by motor rotation is connected between a first pump (mechanical pump) driven by engine rotation and a hydraulic operation part of the transmission. An apparatus is disclosed in US Pat. In this case, the second pump pressurizes the oil supplied from the first pump and supplies the pressurized oil to the hydraulic operation unit.

JP2015-200369A

  By the way, a motor rotates a 2nd pump by being driven by the motor drive part which mounted electronic components (for example, a microcomputer and a capacitor | condenser). In this case, the thermal life of the motor drive unit including the electronic components depends on the temperature of the oil, the ambient environment of the motor and the second pump including the motor drive unit, and the self-heating of the electronic components when the motor is driven. Is done.

  Therefore, in order to extend the thermal life of the motor drive unit, it is desirable to use the motor drive unit within an appropriate temperature range. Specifically, a threshold temperature (a predetermined temperature set lower than the use limit temperature of the electronic component) corresponding to the target life (specified life) is set in advance so that the temperature of the motor drive unit does not exceed the threshold temperature. Control (limit) the motor output.

  As described above, when the threshold temperature is set with a margin between the use limit temperature and the threshold temperature, when the motor is used under a severe heat load, the temperature of the motor drive unit reaches the threshold temperature. And the actual life of the motor drive unit is shortened. On the other hand, when the motor is used under a condition where the heat load is small, the original ability of the motor cannot be fully exhibited.

  In addition, since the electronic components used in the motor drive unit deteriorate due to exposure to heat, it is important to properly control the motor while accurately grasping the heat load of the motor drive unit. It is considered essential for extending the service life.

  The present invention is a further improvement of the hydraulic control device disclosed in Patent Document 1. A hydraulic control device that can appropriately use the motor drive unit until the target life is achieved even under various usage methods and environmental conditions. The purpose is to provide.

  The present invention is a hydraulic control device that supplies oil from a pump driven by a motor to a hydraulic operation unit of a transmission, and includes a motor drive unit, a temperature acquisition unit, a thermal deterioration degree calculation unit, a restriction start temperature setting unit, a temperature It has a determination part and a motor control part.

  The motor driving unit drives the pump by driving the motor. The temperature acquisition unit acquires the temperature of the motor driving unit. The thermal deterioration degree calculation unit calculates a thermal deterioration degree of the motor driving unit based on the temperature. The restriction start temperature setting unit sets a restriction start temperature for restricting the output of the motor based on the degree of thermal degradation. The temperature determination unit determines whether or not the temperature has reached the limit start temperature. The motor control unit limits the output of the motor via the motor drive unit when the temperature determination unit determines that the temperature has reached the limit start temperature.

  In this manner, the limit start temperature is set according to the degree of thermal degradation, and the output of the motor is controlled (limited) within a temperature range equal to or less than the set limit start temperature. This makes it possible to properly use the motor drive unit until the target life even under various usage methods and environmental conditions. As a result, for example, by applying the above-described determination method in a short-term use state, variation in actual life due to differences in use method and environmental conditions can be suppressed, and the motor before reaching the target life. The probability that the drive unit reaches the thermal life (the probability that the motor drive unit fails) can be reduced.

  Here, the temperature acquisition unit may acquire the temperature sequentially and create an approximate line of the temperature up to the current time using the sequentially acquired temperature. In this case, the temperature determination unit determines whether the current temperature acquired by the temperature acquisition unit or the approximate value of the current temperature on the approximate line has reached the limit start temperature. Thereafter, when the temperature determination unit determines that the temperature or the approximate value has reached the limit start temperature, the motor control unit limits the output of the motor.

  As a result, if either the temperature or the approximate value reaches the limit start temperature, the motor output limit is started immediately, so the motor drive unit fails before the target life is reached. The probability of performing can be reduced efficiently.

  In this case, the motor control unit obtains an average value of the motor output within a predetermined time when the temperature is sequentially acquired for creating the approximate line, and the maximum output value of the motor after the output of the motor is limited. Should be set. Thereby, the said temperature can be reduced from the said restriction | limiting start temperature after the output restriction | limiting of the said motor.

  In addition, the motor control unit may stop the output of the motor after the output of the motor is limited, when a required output for the motor is equal to or greater than the maximum output value.

  As a result, both the maintenance of the fuel consumption of the vehicle equipped with the transmission that is limiting the output of the motor, the reduction of the temperature from the limit start temperature, and the use of the motor drive unit until the target life are realized. It becomes possible to do.

Furthermore, the temperature determination unit may determine whether the temperature and the approximate value have fallen below a limit release temperature set below the limit start temperature after limiting the output of the motor. When the temperature determination unit determines that the temperature and the approximate value have decreased below the limit release temperature, the motor control unit may release the output limit of the motor. Thereby, the motor can be quickly returned from the output restriction state to the normal operation state.

  Furthermore, the thermal deterioration degree calculation unit may calculate the thermal deterioration degree based on the temperatures sequentially acquired by the temperature acquisition unit. In this case, the restriction start temperature setting unit may calculate the degree of thermal degradation calculated based on an ideal change over time of the degree of thermal degradation with respect to a usage time of the motor driving unit or a travel distance of a vehicle equipped with the transmission. Is exceeded, the currently set limit start temperature is decreased, while when the calculated thermal deterioration degree is lower than the ideal change over time, the currently set limit start temperature is decreased. Raise.

  Thereby, in the long-term use state, when the degree of thermal degradation is progressing, the restriction start temperature is lowered so that the output restriction of the motor is easily applied. On the other hand, when the degree of thermal deterioration has not progressed, the limit start temperature is increased and the motor is set to continue the normal operation state. As a result, it is possible to use the motor drive unit until the target life while preventing the motor drive unit from being exposed to a high temperature state.

  According to the present invention, the limit start temperature is set according to the degree of thermal deterioration, and the output of the motor is controlled (limited) within a temperature range equal to or less than the set limit start temperature. As a result, the motor drive unit can be appropriately used up to the target life even under various usage methods and environmental conditions.

It is a block diagram of the hydraulic control apparatus which concerns on this embodiment. It is a flowchart in the short-term operation | movement of the hydraulic control apparatus of FIG. 6 is a timing chart showing changes in motor output and driver temperature in a short-term operation. It is a flowchart in the long-term operation | movement of the hydraulic control apparatus of FIG. It is a figure which shows typically the failure probability of the electronic component of FIG. It is explanatory drawing which illustrated the count process of the temperature of a driver. It is explanatory drawing which illustrated the cumulative frequency of the temperature of a driver. It is explanatory drawing which illustrated the relationship between a thermal degradation degree and a target life consumption line. 9A and 9B are explanatory diagrams illustrating the relationship between the operating point of the second pump and the limit line.

  Hereinafter, preferred embodiments of a hydraulic control apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

[1. Configuration of this embodiment]
FIG. 1 is a configuration diagram of a hydraulic control apparatus 10 according to the present embodiment. The hydraulic control device 10 is applied to, for example, a vehicle 14 equipped with a transmission 12 that is a continuously variable transmission (CVT).

  The hydraulic control device 10 includes a first pump 20 that is driven by the engine 16 of the vehicle 14 and pumps up and pumps oil (hydraulic oil) stored in the reservoir 18. An oil passage 22 is connected to the output side of the first pump 20 to flow the oil pumped from the first pump 20 as the first oil. A line pressure adjusting valve 23 that is a spool valve is provided in the middle of the oil passage 22.

  A low pressure system 24 of the transmission 12 is connected to the oil passage 22 via a line pressure adjusting valve 23 provided on the downstream side of the first pump 20. The low pressure system 24 is a low pressure hydraulic operation unit such as a torque converter to which the first oil is supplied. The line pressure adjusting valve 23 is substantially equal to the pressure of the first oil (output pressure of the first pump 20) P1 flowing through the oil passage 22 via the oil passage 25 branched from the oil passage 22, or from the output pressure P1. Also, oil (third oil) having a lower pressure value P3 is supplied to the low pressure system 24.

  An output pressure sensor (P1 sensor) 26 is disposed downstream of the line pressure adjustment valve 23 in the oil passage 22. The output pressure sensor 26 sequentially detects the output pressure P1, and sequentially outputs a detection signal indicating the detected output pressure P1 to the control unit 28 described later. A second pump 30 is connected to the downstream side of the oil passage 22.

  The second pump 30 is an electric pump that is driven by the rotation of the motor 32 provided in the vehicle 14 and outputs the first oil supplied via the oil passage 22 as the second oil. In this case, the second pump 30 can pressurize the supplied first oil and pump the pressurized first oil as the second oil. The motor 32 rotates under the control of a driver (motor drive unit) 34. The driver 34 controls the driving of the motor 32 based on the control signal supplied from the control unit 28, while the driving state of the motor 32 (for example, the rotational speed of the motor 32 according to the rotational speed Nep of the second pump 30). Nem) is sequentially output to the control unit 28.

  The second pump 30, the motor 32 and the driver 34 constitute an electric pump unit 36. A temperature sensor 38 is disposed in the electric pump unit 36. The temperature sensor 38 sequentially detects the temperature Td of the driver 34 (electronic components constituting the driver 34), that is, the internal temperature of the electric pump unit 36, and sequentially outputs a detection signal indicating the detected temperature Td to the control unit 28. The electronic components constituting the driver 34 are, for example, a microcomputer or a capacitor. Further, the temperature sensor 38 only needs to be able to detect the temperature Td of the driver 34, and may be built in the electric pump unit 36 or may be externally arranged in the electric pump unit 36. Although described later, the temperature sensor 38 is not an essential component.

  An oil passage 40 is connected to the output side of the second pump 30. The oil passage 40 is connected to the high pressure system 42 of the transmission 12. The high pressure system 42 is, for example, a continuously variable transmission mechanism (a high pressure hydraulic operation unit) having a driven pulley and a drive pulley (not shown). A check valve 44 is connected in parallel with the second pump 30 between the two oil passages 22 and 40. The check valve 44 is a check valve provided so as to bypass the second pump 30, and allows oil (first oil) to flow from the upstream oil passage 22 to the downstream oil passage 40. On the other hand, the flow of oil (second oil) from the downstream oil passage 40 to the upstream oil passage 22 is blocked.

  A line pressure sensor 46 is disposed in the oil passage 40. The line pressure sensor 46 sequentially detects the pressure (line pressure) PH of the oil supplied to the high pressure system 42 via the oil passage 40 and sequentially outputs a detection signal indicating the detected line pressure PH to the control unit 28.

  The hydraulic control device 10 further includes an engine speed sensor 48, an oil temperature sensor 50, a vehicle speed sensor 52, and a control unit 28. The engine speed sensor 48 sequentially detects the engine speed New of the engine 16 (according to the speed Nmp of the first pump 20), and outputs a detection signal indicating the detected engine speed New (rotation speed Nmp) to the control unit. 28 sequentially output. The oil temperature sensor 50 sequentially detects the temperature (oil temperature) To of the first oil or the second oil, and sequentially outputs a detection signal indicating the detected oil temperature To to the control unit 28. In FIG. 1, as an example, the case where the temperature of the oil (first oil) stored in the reservoir 18 is detected as the oil temperature To is illustrated. The vehicle speed sensor 52 sequentially detects the vehicle speed V of the vehicle 14 and sequentially outputs a detection signal indicating the detected vehicle speed V to the control unit 28.

  The control unit 28 is a microcomputer such as a CPU that functions as a TCU (transmission control unit) that controls the transmission 12 or an ECU (engine control unit) that controls the engine 16. Then, the control unit 28 reads and executes the program stored in the storage unit 28a, thereby executing a temperature acquisition unit 28b, a temperature determination unit 28c, a motor output calculation unit 28d, a motor control unit 28e, and a thermal deterioration degree calculation unit 28f. And the function of the restriction | limiting start temperature setting part 28g is implement | achieved.

  In the storage unit 28a, detection results corresponding to detection signals input from the various sensors described above to the control unit 28 are sequentially stored. In addition, the processing result of each unit in the control unit 28 is sequentially stored in the storage unit 28a.

  The temperature acquisition unit 28b acquires the temperature Td of the driver 34 (an electronic component) from the temperature sensor 38. Alternatively, the temperature acquisition unit 28b estimates the temperature Tde of the driver 34 using the oil temperature To from the oil temperature sensor 50, and acquires the estimated temperature Tde as the temperature Td. Therefore, in the hydraulic control apparatus 10, if either one of the temperature sensor 38 or the oil temperature sensor 50 is provided, the temperature Td of the driver 34 can be acquired, and therefore the other sensor can be omitted.

  The temperature determination unit 28c determines whether or not the current temperature Td acquired by the temperature acquisition unit 28b has reached the limit start temperature Tc preset by the limit start temperature setting unit 28g. Further, the temperature determination unit 28c reads the data of the temperature Td sequentially acquired by the temperature acquisition unit 28b within the latest predetermined time (for example, several minutes) from the data of the temperature Td stored in the storage unit 28a, An approximate line of the temperature Td is obtained from the read data of the temperature Td, and it is determined whether or not the temperature (approximate value) Ta of the obtained approximate line has reached the limit start temperature Tc. That is, the control unit 28 continues to monitor and record the latest temperature value, and the temperature determination unit 28c creates an approximate line based on those temperature values.

  The motor output calculation unit 28d is necessary for supply from the second pump 30 to the high-pressure system 42 in consideration of the line pressure PH and the amount of oil leakage in the oil passage 40 from the second pump 30 to the high-pressure system 42. The flow rate (required flow rate) Q of the second oil is determined. Then, the motor output calculation unit 28d estimates the rotational speed Nem of the motor 32 necessary for discharging the necessary flow rate Q from the second pump 30 based on the obtained necessary flow rate Q. Further, the motor output calculation unit 28d calculates a command value (command value) PWc of the motor output PW by multiplying the estimated rotation speed Nem by the torque of the motor 32.

  Further, the motor output calculation unit 28d reads out the data of the command value PWc within the latest predetermined time from the data of the command value PWc stored in the storage unit 28a, and the predetermined time from the data of the read command value PWc. The average value PWave of the command value PWc is calculated. That is, the control unit 28 continues to monitor and record the latest motor output PW (its command value PWc), and the motor output calculation unit 28d calculates the average value PWave based on those values.

  Note that the control unit 28 sequentially acquires the rotational speed Nem of the motor 32 from the driver 34. Therefore, the motor output calculation unit 28d calculates the motor output PW by multiplying the acquired rotation speed Nem by the torque of the motor 32, sets the calculated motor output PW to the command value PWc, and continues to monitor and record the motor. The average value PWave may be calculated using the output PW.

  Further, the motor output calculation unit 28d reads the line pressure PH and the output pressure P1 stored in the storage unit 28a, and the differential pressure ΔP between the read line pressure PH and the pressure value P3 of the oil supplied to the low pressure system 24. (ΔP = PH−P3) is calculated. The differential pressure ΔP is a hydraulic pressure necessary for the second pump 30 to pressurize the first oil from the pressure value P3 to the line pressure PH and supply the second oil as the second oil from the oil passage 40 to the high pressure system 42. is there. Further, the motor output calculation unit 28d estimates the pressure value P3 from the transmission capacity required for a lockup clutch (not shown) of the vehicle 14 with reference to a map (not shown) stored in the storage unit 28a, for example.

  Furthermore, the motor output calculation unit 28d determines the operating point of the second pump 30 based on the differential pressure ΔP and the necessary flow rate Q.

  The motor control unit 28e determines whether or not the motor 32 should be controlled using the command value PWc based on the comparison between the command value PWc corresponding to the operating point and the average value PWave, and the control based on the determination result The signal is output to the driver 34. For example, when either the temperature Ta or the temperature Td reaches the limit start temperature Tc first and the command value PWc is equal to or higher than the average value PWave, the motor control unit 28e sets PWc = 0 (the motor 32 A control signal for instructing (stop) is generated and supplied to the driver 34. The limit start temperature Tc is a threshold temperature for limiting the motor output PW (its command value PWc), and is a predetermined temperature set lower than the use limit temperature Tlim of the electronic components of the driver 34.

  The thermal deterioration degree calculation unit 28f reads the data of the temperature Td stored in the storage unit 28a, and calculates the thermal deterioration degree of the driver 34 (an electronic component thereof) based on the read data of the temperature Td. The restriction start temperature setting unit 28g sets the restriction start temperature Tc based on the heat deterioration degree calculated by the heat deterioration degree calculation part 28f.

[2. Operation of this embodiment]
The operation of the hydraulic control apparatus 10 according to the present embodiment configured as described above will be described with reference to FIGS. Here, the short-term hydraulic control processing shown in FIGS. 2 and 3, the long-term hydraulic control processing shown in FIGS. 4 to 8, and other control processing based on such hydraulic control (see FIGS. 9A and 9B). ). In these descriptions, description will be made with reference to FIG. 1 as necessary.

<2.1 Short-term hydraulic control processing>
The short-term hydraulic control process refers to a control process performed by the hydraulic control apparatus 10 that is performed in units of time of several minutes to several tens of minutes, for example.

  Here, after briefly explaining the operation of the hydraulic system from the reservoir 18 to the high-pressure system 42, a short-term hydraulic control process will be described.

(2.1.1 Outline of operation of hydraulic system)
First, when the first pump 20 starts driving due to the driving of the engine 16, the first pump 20 pumps up the oil in the reservoir 18, and starts pumping using the pumped oil as the first oil. The first oil flows through the oil passage 22 via the line pressure adjustment valve 23. The output pressure sensor 26 sequentially detects the pressure (output pressure) P <b> 1 of the first oil flowing through the oil passage 22 and outputs the detection signal to the control unit 28. The engine speed sensor 48 sequentially detects the engine speed New and outputs a detection signal to the control unit 28. Further, the oil temperature sensor 50 sequentially detects the oil temperature To of the oil (first oil) stored in the reservoir 18 and outputs a detection signal to the control unit 28. The vehicle speed sensor 52 sequentially detects the vehicle speed V of the vehicle 14 and outputs a detection signal to the control unit 28.

  When the motor 32 is not driven, the first oil flowing through the oil passage 22 flows to the oil passage 40 via the check valve 44. As a result, the first oil is supplied to the high-pressure system 42 via the oil passages 22 and 40. The line pressure sensor 46 sequentially detects the pressure (line pressure PH) of the first oil supplied to the high pressure system 42 and outputs the detection signal to the control unit 28. The line pressure adjusting valve 23 allows the oil passage 22 and the oil passage 25 to communicate with each other and to supply the first oil as the third oil to the low pressure system 24 when the spool valve is displaced by the line pressure PH. It becomes.

  Next, when the supply of a control signal from the motor control unit 28e of the control unit 28 to the driver 34 is started in the state where the first pump 20 is driven, the driver 34 is driven by the motor 32 based on the control signal. And the second pump 30 is rotated. Thereby, the 2nd pump 30 outputs the 1st oil which flows through oil path 22 as the 2nd oil. As a result, the second oil is supplied to the high pressure system 42 via the oil passage 40.

  When the flow rate of the second oil (the discharge flow rate of the second pump 30) exceeds the flow rate of the first oil (the discharge flow rate of the first pump 20), the oil pressure on the oil passage 40 side (line The pressure PH) becomes higher than the oil pressure (output pressure P1) on the oil passage 22 side. As a result, the check valve 44 is closed, and the supply of the first oil from the first pump 20 to the high pressure system 42 via the check valve 44 is transferred from the second pump 30 to the high pressure system 42 via the oil passage 40. Switch to the second oil supply. As a result, the flow of the first oil to the oil passage 40 is blocked, and the second oil is pumped to the high pressure system 42 by the second pump 30.

  The line pressure sensor 46 sequentially detects the pressure of the second oil supplied to the high pressure system 42 as the line pressure PH, and outputs a detection signal to the control unit 28. Further, the driver 34 sequentially outputs the rotation speed Nem of the motor 32 corresponding to the rotation speed Nep of the second pump 30 to the control unit 28. The temperature sensor 38 sequentially detects the temperature Td of the driver 34 and outputs the detection signal to the control unit 28.

  A detection signal from each sensor and a signal from the driver 34 are sequentially input to the control unit 28. The storage unit 28a stores a detection result corresponding to the detection signal sequentially input, and a rotation speed Nem (Nep) corresponding to the signal from the driver 34.

(2.1.2 Hydraulic control process up to time t0 in FIG. 3)
In such an operating state, the control unit 28 performs a short-term hydraulic control process shown in FIGS. FIG. 2 is a flowchart showing a short-term hydraulic control process of the hydraulic control apparatus 10 including the control unit 28, and FIG. 3 is a command of each temperature Ta, Td and motor output PW (in the short-term hydraulic control process). It is a timing chart which shows the time change of value PWc). The flowchart of FIG. 2 is repeatedly executed at predetermined time intervals.

  In this case, the restriction start temperature setting unit 28g presets a predetermined temperature lower than the use limit temperature Tlim as the restriction start temperature Tc, and presets a predetermined temperature equal to or lower than the restriction start temperature Tc as the restriction release temperature Te. The setting of the limit start temperature Tc will be described later.

  The temperature acquisition unit 28b acquires the temperature Td from the temperature sensor 38 at a predetermined time interval, or estimates the temperature Tde of the driver 34 based on the oil temperature To from the oil temperature sensor 50, and the estimated temperature Tde Is obtained as the temperature Td. The acquired temperature Td is stored in the storage unit 28a. In addition, the temperature acquisition unit 28b reads, from the storage unit 28a, the data of the temperature Td that is sequentially acquired at a predetermined time interval within a predetermined time nearest to the current time (for example, a time within several minutes from the current time). Then, an approximate line (temperature Ta) of the temperature Td is calculated from the read data of the temperature Td.

  On the other hand, the motor output calculation unit 28d calculates the motor output PW (the command value PWc thereof) by multiplying the rotation speed Nem of the motor 32 estimated based on the line pressure PH by the torque of the motor 32 at predetermined time intervals. . The calculated command value PWc is stored in the storage unit 28a. Further, the motor output calculation unit 28d reads out the data of the command value PWc calculated within the predetermined time nearest to the current time at a predetermined time interval from the storage unit 28a, and calculates the average value from the read data of the command value PWc. PWave is calculated.

  FIG. 3 illustrates a case where the temperature Td of the driver 34 and the temperature Ta of the approximate line increase with time, and the command value PWc increases or decreases around the average value PWave as time elapses until time t0. In FIG. 3, the time to time t0 is about several minutes, and the temperature Ta indicates the value of an approximate line obtained from the time change of the temperature Td in the last few minutes of time t0.

  In step S1 of FIG. 2, the temperature determination unit 28c determines whether or not the temperature Td of the driver 34 is equal to or higher than the limit start temperature Tc. Since Td <Tc in the time zone up to time t0 (step S1: NO), in the next step S2, the temperature determination unit 28c determines whether or not the temperature Ta of the approximate line is equal to or higher than the limit start temperature Tc. judge. Since Ta <Tc in the time zone up to time point t0 (step S2: NO), the temperature determination unit 28c determines that the temperatures Ta and Td have not reached the limit start temperature Tc.

  In the next step S3, the motor control unit 28e receives the negative determination result from the temperature determination unit 28c, and uses the motor output PW (the command value PWc) calculated by the motor output calculation unit 28d as a command to the motor 32. Set to the value PWc.

  In step S4, the temperature determination unit 28c determines whether or not the temperature Td and the approximate line temperature Ta are equal to or lower than the restriction release temperature Te. As shown in FIG. 3, in the time zone up to t0, Td> Te and Ta> Te (step S4: NO). The motor control unit 28e receives a negative determination result from the temperature determination unit 28c, and outputs a control signal corresponding to the command value PWc to the driver 34.

  Accordingly, the driver 34 drives the motor 32 according to the command value PWc indicated by the control signal supplied from the motor control unit 28e, and rotates the second pump 30. As a result, the second oil is continuously supplied to the high-pressure system 42 by the second pump 30 (normal operation state).

(2.1.3 Hydraulic control process at time t0)
Next, when the temperature Ta of the approximate line reaches the limit start temperature Tc earlier than the temperature Td of the driver 34 at time t0 in FIG. 3 (step S1: NO, step S2: YES), step S5 in FIG. In step S2, the motor control unit 28e receives the positive determination result (Ta ≧ Tc) in step S2, and determines whether or not the command value PWc is equal to or greater than the average value PWave.

  When PWave ≦ PWc is satisfied in step S5 (step S5: YES), in next step S6, when the motor control unit 28e drives the motor 32 and the second pump 30 in accordance with the command value PWc, Judge that the thermal degradation of the parts will proceed. Then, the motor control unit 28e sets the command value PWc to 0 in order to stop the motor 32.

  Next, the temperature determination part 28c determines whether it is Td <= Te and Ta <= Te in step S4. In this case, since Td> Te and Ta> Te (step S4: NO), the motor control unit 28e receives the negative determination result in step S4, and responds to the command value PWc = 0 set in step S6. The control signal is output to the driver 34.

  Thereby, the driver 34 stops the motor 32 according to the command value PWc indicated by the control signal supplied from the motor control unit 28e, and stops the second pump 30. As a result, the supply of the second oil to the high pressure system 42 by the second pump 30 is stopped, and the supply is switched from the first pump 20 to the supply of the first oil to the high pressure system 42 via the check valve 44.

(2.1.4 Hydraulic control process after time t0)
When the temperature Ta or the temperature Td is equal to or higher than the limit start temperature Tc after the time point t0 in FIG. If the command value PWc is equal to or greater than the average value PWave in step S5 (step S5: YES), PWc = 0 is set in step S6, while the command value PWc is less than the average value PWave (step S5). In S5: NO), the command value PWc is maintained. If Td> Te or Ta> Te in the next step S4 (step S4: NO), the motor control unit 28e sends a control signal corresponding to the command value PWc set in step S3 or step S6 to the driver 34. Output.

  That is, in the control unit 28, after the time t0, in order to reduce the temperature Td of the driver 34 and the temperature Ta of the approximate line, an output limiting process is performed to limit the maximum value of the motor output PW (its command value PWc) to the average value PWave. Run. As a result, by repeatedly executing the processing of FIG. 2, the average value PWave decreases with time, and the temperatures Ta and Td can be gradually decreased. In FIG. 3, a motor output PWr indicated by a broken line after time t0 indicates a time change of the command value PWc when the maximum output value is limited to the average value PWave.

  Then, in the flowchart of FIG. 2, when the temperature Td and the approximate line temperature Ta become equal to or lower than the restriction release temperature Te (step S4: YES), the motor control unit 28e performs output restriction processing on the motor 32 in step S7. To release. Thereby, in the next process of FIG. 2, it becomes possible to control the motor 32 and the 2nd pump 30 based on the command value PWc which the motor output calculation part 28d calculated.

<2.2 Long-term hydraulic control processing>
The long-term hydraulic control process is performed every predetermined period (for example, every several months if the target life is a period of several tens of years or a traveling distance of several hundred thousand km). Or the control processing by the hydraulic control apparatus 10 performed every several thousand km).

  FIG. 4 is a flowchart showing a long-term hydraulic control process. FIG. 5 is an explanatory diagram showing the damage probability distribution of the electronic components of the driver 34 with respect to the travel distance of the vehicle 14 or the usage time of the driver 34. The travel distance is obtained by multiplying the vehicle speed V detected by the vehicle speed sensor 52 and time.

  Here, the damage probability distribution Pd indicates the distribution of the damage probability of the electronic component alone, and the damage probability distribution Pr is the distribution of the damage probability of the electronic component when the driver 34 incorporating the electronic component is actually operated. is there. In this case, in any failure probability distribution Pd, Pr, the failure probability becomes maximum at the time point t1 (depending on the distance). However, the breakage probability distribution Pr has a relatively high breakage probability even when the travel distance or use time is shorter than the breakage probability distribution Pd. Therefore, in the failure probability distribution Pr, the actual life of the electronic component may be shorter than the target life. Therefore, it is necessary to devise in order to make the failure probability distribution Pr as close as possible to the failure probability distribution Pd.

  Therefore, the hydraulic control apparatus 10 executes the processing of the flowchart of FIG. 4 for each predetermined period or for each predetermined travel distance, thereby extending the actual life of the driver 34 including the electronic components to the target life and causing damage. The probability distribution Pr is made closer to the failure probability distribution Pd.

  Specifically, in step S11 of FIG. 4, the temperature acquisition unit 28b reads the data of the temperature Td of the driver 34 stored in the storage unit 28a. FIG. 6 illustrates a part of each temperature Td read from the storage unit 28a (each temperature Td at time points t2 to t5) in time series. In the next step S12, the thermal deterioration degree calculation unit 28f creates a cumulative frequency (histogram) for each predetermined temperature shown in FIG. 7 for the read data of each temperature Td.

  In FIG. 7, the horizontal axis is the estimated lifetime, and the vertical axis is the temperature Td of the driver 34 (its electronic component). The thermal deterioration degree calculation unit 28f extracts temperature data equal to or higher than the threshold temperature Tth from the data of each temperature Td shown in FIG. 6, and allocates the temperature Td indicated by the extracted temperature data to the corresponding temperature Td in FIG. (Count). Therefore, in FIG. 7, the bar graph extending on the horizontal axis indicates the cumulative frequency at a certain temperature Td. In FIG. 7, the straight line that decreases as the estimated lifetime increases indicates the thermal lifetime line L. Therefore, when the cumulative frequency at an arbitrary temperature Td exceeds the thermal life line L, it is determined that the electronic component has reached a specified life Tl (target life) corresponding to the threshold temperature Tth.

  In the next step S13, the thermal deterioration degree calculation unit 28f calculates the thermal deterioration degree as an integrated value of the cumulative frequency by bundling (summing up) the cumulative frequencies at the respective temperatures Td in FIG.

  In the next step S14, the heat deterioration degree calculation unit 28f determines whether or not the heat deterioration degree is advanced from the target life consumption line La in the map of FIG. 8 created using the specified life Tl. The target life consumption line La is an ideal change line with time of the degree of thermal deterioration until the electronic component reaches the specified life Tl. A curve Lp shown in FIG. 8 is a line indicating a change in the actual degree of thermal degradation of the driver 34.

  Specifically, the thermal degradation degree calculation unit 28f plots the thermal degradation degree corresponding to the travel distance of the vehicle 14 or the usage time of the driver 34 in the travel distance and thermal degradation degree map shown in FIG. The deviation between the degree of deterioration and the target life consumption line La (deviation = heat deterioration degree−target life consumption line La) is obtained.

  In this case, if the degree of thermal deterioration exceeds the target life consumption line La (step S14: YES, for example, in the case of a positive deviation range Dp), the thermal deterioration degree calculation unit 28f sets the target for the thermal deterioration of the electronic component. It is determined that it is earlier than the life consumption line La. In the next step S15, the limit start temperature setting unit 28g reduces the currently set limit start temperature Tc based on the positive determination result in step S14.

  On the other hand, if the degree of thermal deterioration is lower than the target life consumption line La (step S14: NO, for example, in the case of a negative deviation area Dm), the heat deterioration degree calculating unit 28f determines that the heat deterioration of the electronic component is the target life. It is determined that it is slower than the consumption line La. In the next step S16, the limit start temperature setting unit 28g increases the currently set limit start temperature Tc based on the negative determination result in step S14.

  Thereby, in the next step S17, the temperature determination unit 28c performs a determination process on the temperature Td of the driver 34 using the limit start temperature Tc newly set by the limit start temperature setting unit 28g, and the motor control unit 28e. In response to the determination result, the command value PWc may be set. In step S17, the process of FIG. 2 may be executed.

<2.3 Control Switching According to Discharge Performance of Second Pump 30>
As described above, since the motor 32 can be controlled from the motor control unit 28e via the driver 34, the motor control unit 28e can also perform control processing as shown in FIGS. 9A and 9B. 9A and 9B are diagrams showing the relationship between the required flow rate Q of oil (second oil) supplied to the high-pressure system 42 and the differential pressure ΔP. In FIG. 9A, Llim is a limit line of the discharge performance of the second pump 30. 9A and 9B, the alternate long and short dash line is based on the driving state of the vehicle 14, and the minimum horsepower required to maintain the current driving state, that is, for the vehicle 14 to travel normally in the current state. The equal horsepower lines α to γ (= ΔP × Q) which are necessary engine outputs are shown.

  In FIG. 9A, Pb <b> 1 to Pb <b> 3 indicate operating points of the second pump 30. Since the operating point Pb1 is inside the limit line Llim (a differential pressure ΔP lower than the limit line Llim and a small required flow rate Q), the second pump 30 can be operated. Accordingly, the motor control unit 28e sets the command value PWc corresponding to the operating point Pb1, and supplies the control signal indicating the set command value PWc to the driver 34, thereby driving the motor 32 and driving the second pump 30. Rotate.

  The operating point Pb2 is outside the limit line Llim. Therefore, the motor control unit 28e decreases the differential pressure ΔP to move the operating point Pb2 to the limit line Llim, and supplies a control signal of the command value PWc corresponding to the operating point Pb2 after the movement to the driver 34. Thereby, the driver 34 drives the motor 32 in a state where the output is limited based on the command value PWc, and rotates the second pump 30. Thereby, the 2nd pump 30 outputs the comparatively low pressure 2nd oil in which the pressure was restricted.

  The operating point Pb3 is outside the limit line Llim, but cannot be moved to the limit line Llim even if the differential pressure ΔP is reduced. In this case, the motor control unit 28e determines that the control (required output) exceeds the discharge performance of the second pump 30, and supplies a control signal corresponding to PWc = 0 to the driver 34. As a result, the driver 34 stops the motor 32 and stops the second pump 30. Thereby, the supply of the second oil from the second pump 30 to the high-pressure system 42 is switched to the supply from the first pump 20 to the high-pressure system 42 via the check valve 44.

  FIG. 9B illustrates a case where the outputs of the motor 32 and the second pump 30 are limited by the hydraulic control process of FIG. In this case, the limit line moves from Llim1 to Llim2. As a result, since any of the operating points Pb4 to Pb6 exceeds the limit line Llim2, the control (request output) exceeds the discharge performance of the second pump 30. Accordingly, the motor control unit 28e supplies a control signal corresponding to PWc = 0 to the driver 34, and the driver 34 stops the motor 32 and stops the second pump 30. Thereby, the supply of the second oil from the second pump 30 to the high pressure system 42 is switched to the supply from the first pump 20 to the high pressure system 42 via the check valve 44.

[3. Effects of this embodiment]
As described above, according to the hydraulic control apparatus 10 according to the present embodiment, the limit start temperature Tc is set according to the degree of thermal deterioration, and the motor output PW (within the temperature range below the set limit start temperature Tc ( Command value PWc) is controlled (restricted). As a result, the driver 34 can be appropriately used up to the target life even under various usage methods and environmental conditions. As a result, in a short-term use state, variations in actual life due to differences in use method and environmental conditions are suppressed, and the probability that the driver 34 reaches the thermal life before reaching the target life (the probability that the driver 34 will fail) ) Can be reduced.

  Further, when either the temperature Td or the approximate line temperature Ta reaches the limit start temperature Tc, the motor output PW (the command value PWc thereof) is immediately limited, so before reaching the target life The probability that the driver 34 will fail can be reduced efficiently.

  Further, by setting the average value PWave within a predetermined time at which the temperature Td that is the basis of the temperature Ta of the approximate line is sequentially acquired to the maximum output value after the motor output PW (the command value PWc thereof) is limited, After the start, the temperatures Ta and Td can be lowered from the limit start temperature Tc.

  Further, when the motor output PW is limited, if the required output (command value PWc) for the motor 32 is equal to or greater than the maximum output value (average value PWave), the motor 14 is stopped by setting PWc = 0. It is possible to achieve both the maintenance of the fuel consumption, the reduction of the temperatures Ta and Td from the limit start temperature Tc, and the use of the driver 34 until the target life.

  Further, after the motor output PW is limited, if the temperatures Ta and Td have dropped below the limit release temperature Te set to the limit start temperature Tc or less, the limit of the motor output PW is released, so the motor 32 is output. It is possible to quickly return from the restricted state to the normal operating state.

  Furthermore, when the degree of thermal degradation is progressing in a long-term use state, the restriction start temperature Tc is lowered so that the motor output PW is easily restricted. On the other hand, when the degree of thermal degradation has not progressed, the limit start temperature Tc is increased and the motor 32 is set so as to continue the normal operation state. As a result, it is possible to use the driver 34 up to the target life while preventing the driver 34 from being exposed to a high temperature state.

  It should be noted that the present invention is not limited to the above-described embodiment, and it is needless to say that various configurations can be adopted based on the contents described in this specification.

DESCRIPTION OF SYMBOLS 10 ... Hydraulic control apparatus 12 ... Transmission 14 ... Vehicle 16 ... Engine 18 ... Reservoir 20 ... 1st pumps 22, 25, 40 ... Oil path 23 ... Line pressure adjustment valve 24 ... Low pressure system 26 ... Output pressure sensor 28 ... Control unit 28a ... Storage unit 28b ... Temperature acquisition unit 28c ... Temperature determination unit 28d ... Motor output calculation unit 28e ... Motor control unit 28f ... Thermal deterioration degree calculation unit 28g ... Limit start temperature setting unit 30 ... Second pump 32 ... Motor 34 ... Driver 36 ... Electric pump unit 38 ... Temperature sensor 42 ... High pressure system 44 ... Check valve 46 ... Line pressure sensor 48 ... Engine speed sensor 50 ... Oil temperature sensor 52 ... Vehicle speed sensor

Claims (5)

In a hydraulic control device that supplies oil from a pump driven by a motor to a hydraulic operation part of a transmission,
A motor drive unit for driving the pump by driving the motor;
A temperature acquisition unit for acquiring the temperature of the motor drive unit;
Based on the temperature, a heat deterioration degree calculation unit for calculating a heat deterioration degree of the motor driving unit,
A limit start temperature setting unit for setting a limit start temperature for limiting the output of the motor based on the degree of thermal degradation;
A temperature determination unit for determining whether the temperature has reached the limit start temperature;
When the temperature determination unit determines that the temperature has reached the limit start temperature, a motor control unit that limits the output of the motor via the motor drive unit;
I have a,
The temperature acquisition unit sequentially acquires the temperature, and uses the sequentially acquired temperature to create an approximate line of the temperature up to the present time,
The temperature determination unit determines whether the current temperature acquired by the temperature acquisition unit, or an approximate value of the current temperature in the approximate line has reached the limit start temperature,
The said motor control part restrict | limits the output of the said motor, when the said temperature determination part determines that the said temperature or the said approximate value reached the said restriction | limiting start temperature . The hydraulic control device according to claim 1 , wherein
The motor control unit sets an average value of the output of the motor within a predetermined time at which the temperature is sequentially acquired for creation of the approximate line as a maximum output value of the motor after the output of the motor is limited. A hydraulic control device characterized by that. The hydraulic control device according to claim 2 , wherein
The motor control unit, wherein after the output of the motor is limited, the output of the motor is stopped when a required output for the motor is equal to or greater than the maximum output value. In the hydraulic control device according to any one of claims 1 to 3 ,
The temperature determination unit determines whether the temperature and the approximate value have decreased below a limit release temperature set below the limit start temperature after limiting the output of the motor,
The said motor control part cancels | releases the output restriction | limiting of the said motor, when the said temperature determination part determines that the said temperature and the said approximate value fell below the said restriction | limiting cancellation | release temperature. In a hydraulic control device that supplies oil from a pump driven by a motor to a hydraulic operation part of a transmission ,
A motor drive unit for driving the pump by driving the motor;
A temperature acquisition unit for acquiring the temperature of the motor drive unit;
Based on the temperature, a heat deterioration degree calculation unit for calculating a heat deterioration degree of the motor driving unit,
A limit start temperature setting unit for setting a limit start temperature for limiting the output of the motor based on the degree of thermal degradation;
A temperature determination unit for determining whether the temperature has reached the limit start temperature;
When the temperature determination unit determines that the temperature has reached the limit start temperature, a motor control unit that limits the output of the motor via the motor drive unit;
Have
The thermal degradation degree calculation unit calculates the thermal degradation degree based on the temperatures sequentially acquired by the temperature acquisition unit,
The limit start temperature setting unit is when the calculated thermal degradation degree exceeds the ideal time change of the thermal degradation degree with respect to a usage time of the motor driving unit or a travel distance of a vehicle equipped with the transmission. In the case of lowering the currently set limit start temperature, on the other hand, if the calculated degree of thermal degradation is lower than the ideal temporal change, the currently set limit start temperature The hydraulic control apparatus characterized by raising.

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